For the large red circled area, I'd like to agree and say that there's a separation of the hangar area from the hall area, the hangar floor probably being one or two 10-ft floors below, and much wider than the hall area.
As for the blue catwalk line, I'd also agree that it ends either at or behind the elevator, and does not continue into the hangar.
For the green line, are you referring to the floor of the hall dipping down when it meets the floor of the hangar, or are you thinking about the desk and the floor being behind it? I've always seen the options desk as being raised above the hall itself, looking down.
see attached:
[attachment deleted by ninja]